<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>血月</title>
    <style>
        .b1 {
            background-color: darkkhaki;
            display: inline-block;
            width: 100px;
            height: 100px;
            /* 渐变 */
            transition: all 2s linear 0s;
        }
        
        .b1:hover:hover{
            /* 圆角 */
            border-radius: 50%;
            /* 阴影 inset内嵌  x轴偏移量 y轴偏移量 模糊半径 颜色 */
            box-shadow: inset 10px 10px 10px lightgray;
        }

    </style>
</head>
<body>
    <div class="b1"></div>

</body>
</html>